Replaced [docgen:wd] with [docgen.wd].
diff --git a/freemarker-docgen-core/src/main/java/org/freemarker/docgen/core/PrintTextWithDocgenSubstitutionsDirective.java b/freemarker-docgen-core/src/main/java/org/freemarker/docgen/core/PrintTextWithDocgenSubstitutionsDirective.java
index 3975c43..b245e94 100644
--- a/freemarker-docgen-core/src/main/java/org/freemarker/docgen/core/PrintTextWithDocgenSubstitutionsDirective.java
+++ b/freemarker-docgen-core/src/main/java/org/freemarker/docgen/core/PrintTextWithDocgenSubstitutionsDirective.java
@@ -127,7 +127,7 @@
         new DocgenSubstitutionInterpreter(text, env).execute();
     }
 
-    private static final String DOCGEN_WD_TAG = "[docgen:wd]";
+    private static final String DOCGEN_WD_TAG = "[docgen.wd]";
     private static final Pattern DOCGEN_WD_TAG_AND_SLASH_PATTERN = Pattern.compile(Pattern.quote(DOCGEN_WD_TAG) +  "/?");
 
     private class DocgenSubstitutionInterpreter {